反应详情

To the suspension of 4-(2,6-difluoro-phenyl)-1H-indole (9.5 g, 41.4 mmol) in t-BuOH: ethanol: acetic acid (262 mL: 155 mL: 81 mL) was added pyridinium tribromide (40.28 g, 126 mmol) portionwise. The mixture was stirred at room temperature for 3 hours, and then to the mixture was added more acetic acid (200 mL). Zinc dust (14.2 g, 217 mmol) was added to the reaction mixture portionwise. After stirring for one hour, the unreacted zinc was filtered off and most of the solvent was removed under reduced pressure. The residue was diluted with ethyl acetate, washed with water (5×), sat. NaHCO3 (2×), brine (3×), dried over Na2SO4, concentrated, triturated with ether to give 7.1 g (70%) of 4-(2,6-difluoro-phenyl)-1,3-dihydro-indol-2-one as a white solid.

1. stirringAfter stirring for one hour
2. filtrationthe unreacted zinc was filtered off and most of the solvent
3. customwas removed under reduced pressure
4. additionThe residue was diluted with ethyl acetate
5. washwashed with water (5×), sat. NaHCO3 (2×), brine (3×)
6. dry with materialdried over Na2SO4
7. concentrationconcentrated
8. customtriturated with ether